Decoy for guided missiles



Jan. 21, 1964 F. H. ROHR DEcoY FOR GUIDED MIssILEs 2 Sheets-Sheet 1Filed Oct. 3l, 1958 INVENTOR.

F. H. R OH R ATTORNEY Jan. 21, 1964 F. H. RoHR DECOY FOR GUIDED MISSILES2 Sheets-Sheet 2 Filed Oct. 31, 1958 INV ENTOR.

F.H.ROHR maw-rz. f

ATTORNEY United States Patent O 3,118,638 DECY FR GUEDED MlSlilLES FredH. Rohr, San Diego, Calif. Filed Oat. 3l, 1958, Ser. No. 77l,t359 2claims. (or. 24e- 1ro This invention relates to a device for diverting aguided missile from an elevated path along which it is moving.

Such missiles are known which are launched from platforms on the groundor released from airplanes in the sky and which are steered toward atarget by suitable control members mounted in them. Each missile alsocarries a charge of high explosive which explodes upon striking thetarget. When the target is an aircraft in iiight, its radio or radartransmitter sends out radio waves of one or more frequencies and its hotexhaust pipe and exhaust gas emit infrared radiations. lf the missile isprovided with a receiver or detector which picks up these radio waves orcurrents or infrared rays, ampliies them and passes the information asto their direction on to the controls of the missile it can be guided tothe target source of radiant energy.

lt is a main purpose of my invention to provide a decoy device whichremains suspended a long time high in the sky and is continuallyradiating Waves which may be picked up by such a guided missile, divertit from the path along Which it is moving, steer it towards the decoyand cause it to collide therewith and explode.

A further object is to provide such a decoy device which is continuallyradiating radio waves capable of controlling the radio controls of aguided missile and also infrared rays capable of operating its othercontrols so that the missile will be guided to the decoy irrespective ofwhich type of wave energy its receiver picks up.

Another object is to provide a decoy of the type described with aballoon which will keep it suspended for a long time at a substantiallyconstant elevation in the sky.

A further object is to provide a hollow casing for the decoy which willcontain and enclose its component parts and is shaped as a rocket whichis self propelled to a high elevation where the balloon and radiantenergy source or sources are expelled from the casing and remainsuspended at a desired high altitude.

Other objects will become apparent as a detailed description of my noveldecoy proceeds. For a better understanding of the invention reference ismade to the accompanying drawings, in which:

FlG. l is a diagram showing the decoy on a tiring platform and atdifferent stages after firing;

FIG. 2 is a longitudinal sectional View through the decoy some of thecomponent parts being shown schematically;

FIG. 3 is a front View of the decoy in operative position in the sky;

FIG. 3a is an enlarged view of the decoy of FIG. 3;

FIG. 4 is a cross section on line 4 4 of FIG. 3a;

FlG. 5 is a circuit diagram of the radio transmitter and infrared lamp;

FIG. 6 is a sectional View of a tuning condenser and a schematic View ofa spring motor for rotating it and;

FlG. 7 is an end view of a rotatable plate of the tuning condenser.

Referring to FIGS. 3 and 3a the decoy comprises a flexible balloon il)which supports a hollow cylindrical casing Il containing a radiotransmitter l2, a spring motor 13, an infrared lamp ld or other sourceof infrared rays and a non-directional antenna l5. The top of casing lllis provided opposite lamp ifi with four large openings or windows 1.6 sothat the infrared rays emitted are radiated in all directions from thesides of the casing. The top of lamp lfi is preferably coated with areiiecting coating lld Patented dan. 2l, 1954 i7 (FIG. 2) which preventsany substantial amount of the emitted rays from traveling up and heatingthe bottom of balloon il).

Referring to FIG. 5, the transmitter illustrated comprises an oscillatortube 18 which has a tuned plate circuit 9 to which current is suppliedby a battery 2li when the switch 2l is closed. Circuit ll@ comprises anadjustable tuning condenser 22 and an inductance coil 23 to which isinductively coupled a feedback coil 24 in the grid circuit 25 which alsoincludes a small battery Z6 for negative grid bias. Condenser 22 (FlGS.6 and 7) comprises a plurality of thin metal plates 27 mounted on arotary shaft 23 supported in insulating bearings 29 carried by a metalsupporting frame 3b. Frame 3@ has a plurality of thin metal statorplates 3l which lie closely adjacent plates 27 and are of substantiallythe same shape as these plates. Spring motor i3 may be of any known typewhich will slowly rotate shaft 2S to cause the frequency of theoscillations generated by tube lill to increase from a minimum frequencyto a maximum frequency at each revolution of shaft 28. The range ofradio frequencies through which the oscillator is tuned includes thefrequency or frequencies to which the resonant radio receiving or inputcircuits of the guided missiles to be captured are tuned. Theoscillations generated by oscillator tube 18 are amplified by amplifiertube 32 whose output circuit is coupled by transformer 33 and lead 34 toantenna l5. Preferably battery Ztl is also used to supply heatingcurrent to lamp 14 through the circuit shown which includes anadjustable resistor 35 which regulates the amount of heating currentsupplied. A suitable filter such as choke coil 36 and condenser 37prevents the radio frequency currents in the plate circuit of amplifier32 from passing through battery 2li and lamp le.

Casing l1 (see FIG. 3a) terminates at its upper end in a cylindricalportion 3S whose upper end tapers out to provide a seat 39 for a ballcheck valve 40. The cylindrical lower end 4l of the balloon fits aroundcasing portion 33 and is secured thereto by cord or wire Wrapping 42.One or more holes 43 are made through casing portion 3S for a purpose tobe described. Valve dll is biased against seat 39 by spring 4d and aflexible wire or cord 45 connects valve lll to the top 46 of the balloonas shown. The balloon is filled with hydrogen or helium in a manner tobe later described and distends as it rises. When it reaches a certainheight, its small ascent above this level would cause its furtherdistention which would cause wire l5 to lift valve dll from its seat 39,permitting some of its contained gas to escape through the openings 43and restore the balloon to its desired maximum size. Means is thusprovided to keep the balloon for a long time approximately at a desiredheight.

To propel the decoy high into the sky, its component parts are stowed ina rocket (see FlG. 2) comprising a generally cylindrical metal casing1257 having the usual guide fins 43. The rear end of the casing containsa charge of solid propellant fuel 49 which can be ignited by 4anysuitable igniter Sti. A metal barrier Sl extends across the casing andis secured thereto as by welding, the center of the barrier supporting ashort fuse 52 adapted to ignite a power charge 53. A circular plate S4separates the powder from the rear or lower end 55 of casing il. Member55 carries an insulating bushing 56 within which antenna l5 is slidable,the top end of the antenna having a stop ilange 57 adapted to engagebushing 56 and limit the outward motion of the antenna under the bias ofspring S3 after the decoy leaves casing 47 as later described. Acylindrical casing l59 extends along the inner face of casing 47, thiscasing being composed of 6 or more separate segments made of polymerizedresin, the sides of each segment abutting the sides of the two f thusclose switch 21.

o? adjacent seg. ents so that casing 59 can easily tall apart after itleaves casing 47.k The top end or" casing 591s provided with a ygroover6i? which receives kan expansible tasas snap ring 6i which retains acircular plasticy disc62 yin position,this disci having a concave `faceagainst which the top'portionof balloon itl presses, as illustrated Disc62 has a suitable opening 63 to provide access to any ltnown type oftillerorchecli valve 64.- to which a hose f may be connectedto fill theballoon with gas under pres-k A detachable 'pointed nosey piece '65 litsagainst' sure. the `ends of casings 47 yand 59 and minimizes the airresistance as the rocket risesy quickly to altitude. kThe movable bladeof switch 21 carriesk al button 66r which protrudes through a smallopeningin casing 11 and rests againstk plastic casing 59 toy retain theswitch in open position before the lrocket is redp A'spring 67 biasesthe switch blade toward elosediposition. f

`To launch the decoyinto the sky ina localityk where enemy guidedmissiles rare expected, kbt'eforenose Cap 615 is applied, balloon isfilled with hydrogen or helium gas toy the desired pressure throughvalve 64.

63 (FIG. 1)and` redby operating igniter 5G. The thrust 'The separationof the lsegments of casing S9 permits button 66 tomove out under thebiasof spring 67 and Current from battery Ztl soon renders oscillator 1S andamplifier 32 operative and since `antenna `is now projecting below thebottom S5 of f ,casingfiL as'shown in FIGS. 3 and 3a, radio1 Wavesaretransmitted in all kdirections from thek antenna and also infraredradiations are propagated in all directionsk out-y wardly from lamp 14,as shown in PEG. 3.' As above explained the frequency 'of the radiowaves transmitted' is slowly varied through a range of frequencies sothat a guided missile controlled by a radio receiver Whose resonantcircuit or circuits are tuned to any frequency within the band offrequencies transmitted by the decoy will be diverted from the pathalong which it is moving and steered toward the decoy until it colli-deswith it. On the other hand if the missile has steering controls operatedby a receiver sensitive to infrared radiations, it will be diverted fromits path, guided to the decoy and destroyed. The decoy will remain inthe sky in the position shown in FIG. 3 for a long time until the springmotor 13 runs down or the battery 26 becomes exhausted. Instead ofspring motor 13, an electric motor operated by current from battery 26could be used to rotate a gear reducer (not shown) which rotates shaft28 slowly.

This invention may be embodied in other forms or carried out in otherways without departing from the spirit or essential characteristicsthereof. The present embodiment of the invention is therefore to beconsidered as in all respects illustrative and not restrictive, thescope of the invention being indicated by the appended claims, and allchanges which come within the meaning and range of equivalency of theclaims are intended to be embraced therein.

Cap r65' is ythen attached and the rocket put on a launching platformHavingthns described my invention, what Iclaim as new and useful anddesire to secure by Letters Patentis: 1. A device for` diverting aguided missile from a path along which it is movingin response toelectromagnetic waves picked up thereby froma, target comprising:y aninflated-balloon; a casing depending from said balloon n f said casingkhaving a wall` provided with a plurality of op` positely disposedopenings of large yarea therein; yand a kcontinuous source ofelectromagnetic waves` of intensity comparable to those emitted by ksaidtarget disposed within said casing, said source ycomprisingfa batteryand an kinfrared lamp yenergized from said battery and mounted `Withinsaid casing opposite said openings .for emitting; and

radiating infraredrays through said openings in substanf tially alldirections from the sides of said casing.

2. A .decoy fordiverting a guided missile froman ele- .vated path alongkwhich it is moving comprising: ahollow casing having a detachable capat its upperend; rocket means having a kcharge of solidk propellantfuel` and an igniter therefor associated Awithy saidcasing forypropelling it to a predetermined high altitudefrorn a launchingstationk wheny the igniter is ignited andthe charge is tired; a

housing disposed within said casing and comprisingy ay plurality ofseparable members, a balloon disposed and continedfwithin said` housingandhaving a quantity of f gas under pressure therein; means connected'tosaid balloon and kadapted to be sLpportedy thereby yfor radiatingrsignals forguiding a guided missile to said decoy, saidy radiatingmeans being kdisposed within said housing, means operable in timedelayed relation to the launchingof `said f decoy for ejectingsaid cap`and` said separable housing from said casing thereby/.to release saidballoon` and .said` radiating means .from the khousing .and to distendthe balloon as saidinembers separate in response tothe pressure of theballoon` thereon, and valve means disposed Within `said balloon. andresponsive. to a predetermined distentionthereof in excesszof thatobtainable at said n predeterminedl altitude. for, effecting partialdeflation of ythe balloon suticient to maintain the` same at saidpredetermined altitude, saidejectingmeans comprising a powder charge anda fuse for tiring the same disposed within said solid charge remotelyfrom said igniter therefor.

References Cited in the tile of this patent UNITED STATES PATENTS 39,636Felt Aug. 25, 1863 2,027,367 Blair Jan. 14, 1936 2,192,450 Miller Mar.5, 1940 2,341,351 Barkley Feb. 8, 1944 2,381,443 Golay Aug. 7, 19452,397,114 Anzalone Mar. 26, 1946 2,405,134 Brown et al. Aug. 6, 19462,447,972 Weinert Aug. 24, 1948 2,587,564 Williams Feb. 26, 19522,603,433 Noslter July 15, 1952 2,655,649 Williams Oct. 13, 19532,861,165 Aigrain et al. Nov. 18, 1958 2,869,120 Lolniaugh Jan. 13, 19592,913,983 Lytel Nov. 24, 1959 2,987,269 Weller June 6, 1961

1. A DEVICE FOR DIVERTING A GUIDED MISSILE FROM A PATH ALONG WHICH IT ISMOVING IN RESPONSE TO ELECTROMAGNETIC WAVES PICKED UP THEREBY FROM ATARGET COMPRISING: AN INFLATED BALLOON; A CASING DEPENDING FROM SAIDBALLOON SAID CASING HAVING A WALL PROVIDED WITH A PLURALITY OFOPPOSITELY DISPOSED OPENINGS OF LARGE AREA THEREIN; AND A CONTINUOUSSOURCE OF ELECTROMAGNETIC WAVES OF INTENSITY COMPARABLE TO THOSE EMITTEDBY SAID TARGET DISPOSED WITHIN SAID CASING, SAID SOURCE COMPRISING ABATTERY AND AN INFRARED LAMP ENERGIZED FROM SAID BATTERY AND MOUNTEDWITHIN SAID CASING OPPOSITE SAID OPENINGS FOR EMITTING AND RADIATINGINFRARED RAYS THROUGH SAID OPENINGS IN SUBSTANTIALLY ALL DIRECTIONS FROMTHE SIDES OF SAID CASING.